Electrically-heated device.



W. S. HADAWAY, JR. ELEOTRIGALLY HEATED DEVICE. APPLICATION FILED MAY 1, 1909.

977,625. Patented Dec. 6,1910.

2 SHEETS-SHEBT l:

INVENTORY ATTORNEY Y, JR. ELECTRIGALLY HEATED DEVICE. API LIOATION FILED MAY II 1909.

.w. s. HADAWA Patented Dec 6 ATTORN EY WITNESSES:

- UNITED STATES PATENT onmon."

WILLIAM S; HADAWAY, JR., OF EA$T ORANGE, .h EXV JERSEY. ASSIGNOR TO WESTING- HOUSE ELECTRIC .AND MANUFACTURING COMPANY, A CORPGRATION OF PENN- SYLVA'NIA.

ELECTRICALLY-HEATED DEVICE.

Specification ef Letters LPatent.

Application filed May 1, 1909. Serial No. 493,408.

T 0 all whom it may concern:

Be it known that I, lVILLIAM S.I'IADAWAY, J12, a citizen of the United States, and a resident of East Orange, in the county of Essex and State of New Jersey, have invented a new and useful Improvement in Electrically-Heated Devices, of which the following is a specification.

My inv ion relates to electrically heated laundry r0 and similar devices, and it has for its obj ect to provide a device of this character that shall be simple and durable in construction and in which a ll'lZlXlll'lUlD amount oi the generated heat is conducted to the working surfaces.

Nhen laundry rolls and other hollow cylindrical bodies are heated electrically, itis usual to place the resistance or heater ele ment within the cylinder but it is di'l'licult to obtain a good contact between the inner surface of the cylinder and the heater without injuring the heater in assembling the device.

In order to overcome the above mentioned r difliculty, I provide, according to one emthe resistance element and the inner cylinder.

Figure l of the accompanying drawings is an end elevation of a roll constructed in accordance with 'my invention. Fig. 2 is a sectional view eta portion oi. the roll shown in Fig. l, and Fig. is a sectional view, on an enlarged scale, of one wall of the seinbled device. Fig. 4: is a detail view oi the resistance or heater element employed in the device shown in the other figures. Figs. 5, 6 and 7 are views, corresponding to Figs. 1, 2 and 3, of a modified structure which embodies my invention Referring to Figs. 1., 2, 3 and l. of the drawings, the device here illustrated comprises a hollow cylindrical shell 1 of steel or other suitable material, an inner cylinder 2 of brass or some other metal having, a

greater co-eflicient of expansion than that of the shell-l, and a resistance element 3 which is interposed between the shell and the cyl inder and is insulated from each of them.

The insulating cylinder l which is int-en.

posed between the resistance element 3 and the inner surface of the shell 1 is relatively.

thin, while the cylinder 0 which surnunds the inner cylinder and on which t e resistance elen'ient is mounted is relatively thick.

In assembling the device, the resistance element is disposed on the surface of the inner cylinder 2 after it has lJGQJ'l suitably insulated, the resistance element being held in position by an outer wrapping of insulation. The size of the inner cylinder 2 and the thickness of the insulation is such that, when assembled, these parts lit closely into the shell 1.

By making the insulation between the re sistance element and the shell thin, the heat generated in the resistance is largely conducted through the shell to its outer working surface, and, since the insulation between the resistance element and the innercylindcr is relatively thick, the heat is largely prevented from passing into said cylinderQ I hen the device is in operation, all of the parts will obviously become heated to a greater or less degree and, since. the co-eflicient of expansion of the cylinder 2 is greater than that of the shell 1, the resistance element will be forced into very close engagement with. the inner surface of the roll.

Referring to Figs. 5, 6 and 7 the heater Patented Dec. 6, 1910. V

or resistance element 6, as here shown, is

protected by a sheath 7 of thin metal, such as sheet iron, from which it is separated by mica or other suitable insulation. The sheathed resistance is so constructed as to it into the shell 1 and, when it is in position, a plurality-oi interrupted thermostatic rings 8 are fitted into it and are spaced at conveniein'; distances apart. Each of the rings .8 comprises a resistance strip or ribbon 9 and a sheath 10 built up or rods or bars oi unlike metals that are welded together at their edges and are adapted to force the sheathed resistance 6 into close engagement with the inner surface of the element 6 may be connected in circuit to receive heating current in any manner Whlch will insure the desired results. The thermostatic rings 8 are preferably'constructed in the manner set forth in my co-pending application, Serial'No. 493304;, filed of even date herewith.

It is evident that structural modifications may be effected in the device illustrated without departing from the spirit of my invention, and I desire that only such limit-atime shall be imposed asare indicated in an outer shell, a concentric inner cylinder of material having a higher co-efiicient of exansion, and a resistance element interposed etween the shell and the cylinder and insulated from each,

3. An electrically heated device c0mprisin an outer cylinder, a concentric inner cylin er of material havin a greater co-efiicient of expansion, a resistance element in-- terposed between the cylinders, a relatively thick insulating sleeve separating the resistance from the inner cylinder, and a relatively thin insulating sleeve separating the resistance element from the outer cylinder.

4:. An electrically heated device comprising an outer cylinder of iron, a concentric inner cylinder of brass, and a resistance element interposed betweenthe cylinders and insulated. from each. j

5. An electrically heated roll comprising an outer shell of iron, a concentric inner cylinder of brass, a relatively thick insulating slee-ve separating the resistance from the brass cylinder, and a relatively thin insulating sleeve separating the resistance from the iron shell.

6. An electrically heated device comprising a member having a working surface, a resistance element for heating sald member, and a member having a relatively great degree of expansibility when heated, said vexpansible member being located ad'acent to said resistance element and being a apted to force the resistance element into engagement with the member having the working surface when ment. a

In testimony whereof, I have hereunto' subscribed my name this 20th day of April, 1909. I

WVitnesses:

R. J. DEARBOBN, B. B. Hmns.

heat is generated in Said ele- 

